Antony Flew, a celebrated 20th century philosopher, put forth an argument in favor of atheism which states, roughly, that in the absence of any clear evidence for theism, atheism is the rational presumption. I would quibble with this argument, for such a presumption is inherently tied to a positivist view and simply fails to take the idea of God seriously [Flew, it is worth noting, later became a theist after engaging with Aristotle]. However, this model of presumption that lacking evidence for some specific thesis is evidence enough to establish the rationality of disbelief is not necessarily flawed with respect to theses of a less metaphysical scope. For instance, a presumption of “There are no invisible pink unicorns on the dark side of the moon” is something we would consider reasonable, and it would require extremely different metaphysical priors for a nearly-certain probability to not be assigned to that belief. We might consider instances of failure to appropriately weigh negatives to highly specific, highly unlikely instances indicative of a general failure of rationality. That is, such a failure at the fringe might be considered akin to debugging; if you’re unable to both state what would constitute evidence of such a unicorn and to then elaborate on why it would be so unlikely to find evidence of such, you are unlikely to have a solid grasp on sound principles of methodological analysis.
On the other hand, if we were to find such a unicorn on the dark side of the moon, this would highlight that our ordinarily functional rationality has a large blind spot. But, assuming there is no such blind spot [in this specific area of our rational periphery], it proves itself a useful kind of test.
Granted, it is likely almost no one wouldn’t be willing to weight the negative thesis with near-certain probability; it illustrates a principle at an extreme degree. We may also apply such forms of “rational debugging” on other people in more specific ways. It is very easy to have a view of the world which allows one to conclude the near-certain improbability of unicorns being on the dark side of the moon; it is much more difficult to elucidate complex social systems. Consider the following description, which will function as a kind of theoretical litmus test in which I have removed certain key elements.
A specific subpopulation of the greater society is disproportionately represented in prisons.
The explanation you’re likely to reach for is likely to reveal your ideological priors. There are two positive theses which present themselves as likely explanations: either this represents something innate of that population, or it demonstrates that the greater society has a bias towards putting members of that subpopulation in prison. Both of these explanations have concrete instances we can conceive which would serve to verify either of these hypotheses. Those who would tend to offer either explanation and then stick to it despite further information are revealed to have a defect in their rationality; in reality, the above description isn’t sufficient to verify either explanation. The proper response is to admit of both possibilities with an agnosticism dependent on further information, if forthcoming [with a caveat that this might still warrant avoiding that subpopulation if you are unable to access further information].
If the specific subpopulation in question were men, who are indeed disproportionately represented in prison, we are likely to accept the former explanation. That there are more men in prison compared to women is explained by their being innately more aggressive and having a lower aversion to risk, traits which lend themselves to a higher likelihood of criminality. At the same time, we also notice that men are likely to receive harsher sentences than women for the same crimes, which we attribute to this innateness; the more likely a specific subpopulation is to exhibit criminality, the harsher the punishments must be in order to act as a stronger deterrent of that behavior.
Now consider if the specific subpopulation we were speaking of are blacks. Whereas the explanation for why men as a group are more likely to be in prison than women is explained by innate differences, the suggestion that disproportionate representation by blacks is due to innate differences is racist. There is, in other words, a kind of presumption in favor of racism we exercise which we don’t exercise when it comes to men. This isn’t necessarily an indicator of a failure of rationality. After all, we do recognize cases where certain populations are prejudicially incarcerated and overall persecuted. The Nazis persecuted the Jews, Rome persecuted Christians, the Catholic Church persecuted the occasional atheist, Christians persecuted Muslims, Muslims persecuted Christians, so on and so forth for almost every potential pairing of groups. If we find a disproportionate representation of Christians in prison in a self-proclaimed secularistic society, the only innate factor we might attribute to the Christians in this case is a religious zealotry, but not innate factors that make them otherwise predisposed to criminality under sane conditions of legal jurisdiction.
However, our means of distinguishing between which hypothesis serves to explain the disproportionate representation of a subpopulation in prison requires the elucidation of a theory which allows us to test for the mechanisms in place which verify the former or latter hypothesis. If one takes the mere fact of disproportionate representation as proof of unjustified discrimination [disproportionate representation by a group can also occur due to justified discrimination, e.g. those employed by NASA are disproportionately represented by those of 125+ IQ, and with good reason], then we must be forced to conclude that the disproportionate representation by men in prison is not due to innate traits such as greater mean aggression and lower mean risk-aversion, but is the result of a mere prejudice.
After all, the feminists do tell us that women are psychologically essentially the same as men, and criminality is a psychological trait. Either men are overly represented and/or women are underrepresented. Indeed, there are some feminists who even make the argument that patriarchy is a net disadvantage to men, with only a minority of men being benefited; this could be evidence of just such a patriarchy. I don’t know how this male-female disparity could be solved, but it’s worth pointing out that this disparity stands in need of a rigorous, scientific justification.
That said, many would still, and quite reasonably, remain with the hypothesis that men just are more innately prone to criminal behavior. Vis-à-vis criminality, men have a higher mean than women, which is explained by simple biology. Once you accept such an explanation, however, this same theory could also explain the disproportionate representation of blacks in prison. At least in principle, if the theory is sound in terms of explaining the gender disparity, it may explain other group disparities such as racial disparity.
If we are to distinguish between biological and social reasons for group disparities, then we must have some way of measuring those differences. Biological differences in psychology appear to be measurable; for example, exhibited time preference in young children has a correlation to life outcomes. If we are willing to accept that this experiment documents a real, genetically influenced trait, this presents a very simple means of finding evidence for weighing the difference between biological and social means of explaining racial disparities [it must at least document something strongly ingrained by the age of the children being observed]. If no significant difference is found between children by race, this is evidence in favor of the social hypothesis; on the other hand, if there are significant disparities found between race, and those disparities also happens to approximate the differences we find elsewhere in society, that is evidence in favor of the biological hypothesis. [I’m aware of potentially confounding factors; for instance, there was a high correlation between socioeconomic status and ability to delay gratification. This might potentially be explained by the conditions of poverty socializing a child into lower ability to delay gratification. However, this can be controlled for by simply comparing children of similar socioeconomic backgrounds. If anyone can find a study which does so, please send it my way; I searched my usual academic sources and could find nothing.]
Back to Flew and his presumption of atheism. Borrowing a parable from John Wisdom, he writes:
Once upon a time two explorers came upon a clearing in the jungle. In the clearing were growing many flowers and many weeds. One explorer says, “some gardener must tend this plot.” The other disagrees, “There is no gardener.” So they pitch their tents and set a watch. No gardener is ever seen. “But perhaps he is an invisible gardener.” So they, set up a barbed-wire fence. They electrify it. They patrol with bloodhounds. (For they remember how H.G. Wells’s The Invisible Man could be both smelt and touched though he could not he seen.) But no shrieks ever suggest that some intruder has received a shock. No movements of the wire ever betray an invisible climber. The bloodhounds never give cry. Yet still the Believer is not convinced. “But there is a gardener, invisible, intangible, insensible to electric shocks, a gardener who has no scent and makes no sound, a gardener who comes secretly to look after the garden which he loves.” At last the Sceptic despairs, “But what remains of your original assertion? Just how does what you call an invisible, intangible, eternally elusive gardener differ from an imaginary gardener or even from no gardener at all?”